Chronic ethanol and cocaine-induced hepatotoxicity: effects of vitamin E supplementation

Dietary supplementation in patients with alcoholic liver disease: a review on current evidence

BACKGROUND

Alcoholic liver disease (ALD) is one of the main causes of liver disease worldwide. Although the pathogenesis of ALD has not yet been well elucidated, the oxidative metabolites of ethanol such as acetaldehyde and reactive oxygen species play a pivotal role in the clinical and pathological spectrum of the disease. This review summarizes the existing evidences on dietary supplements considered to have antioxidant, and/or anti-inflammatory properties, and their role in the management of ALD and the proposed mechanisms.

DATA SOURCES

The present study reviewed all studies published in PubMed, ScienceDirect and Scopus, from 1959 to 2015, indicating the role of different dietary supplementation in attenuation of many pathophysiological processes involved in development and progression of ALD. Full-texts of citations were used except for those that were published in languages other than English.

RESULTS

Significant progress has been made to understand the key events and molecular players for the onset and progression of ALD from both experimental and clinical studies; however, there is no successful treatment currently available. The present review discussed the role of a variety of dietary supplements (e.g. vitamin A, carotenoids, vitamins B3, C and E, in addition to antioxidants and anti-inflammatory agents) in treating ALD. It has been shown that supplementation with some carotenoids, vitamin B3, vitamin C, silymarin, curcumin, probiotics, zinc, S-adenosylmethionine and garlic may have potential beneficial effects in animal models of ALD; however, the number of clinical studies is very limited. In addition, supplementation should be accompanied with alcohol cessation.

CONCLUSIONS

Since oxidative stress and inflammation are involved in the pathogenesis of ALD, dietary supplements that can modulate these pathologies could be useful in the treatment of ALD. In addition to alcohol cessation, these supplements have shown beneficial effects on animal models of ALD. Clinical trials are needed to validate the beneficiary role of these supplements in patients with ALD.

The role of stimulated lipid peroxidation and impaired calcium sequestration in the enhancement of cocaine induced hepatotoxicity by ethanol

The purpose of this study was to investigate possible mechanism of cocaine-induced hepatotoxicity and its potentiation by ethanol in mice. Ethanol (2 g/kg) and/or cocaine (25 mg/kg) injections were given as binge model (five injections in 3 days). Cocaine administration with or without ethanol caused an increase in lipid peroxidation in liver homogenate and its subcellular fractions. The greatest increases were observed in mitochondrial fraction following cocaine plus ethanol treatment. Also, glutathione (GSH) levels were increased in liver homogenate and its mitochondrial fractions after cocaine and cocaine plus ethanol treatment. Microsomal calcium sequestration was found to decrease in all treatments. These results suggest that increased lipid peroxidation and decreased microsomal calcium sequestration in the liver may play a possible role cocaine-induced hepatotoxicity and its potentiation by ethanol.

A murine model of prenatal cocaine exposure: effects on the mother and the fetus

To develop and characterize a murine model for investigating the long-term effects of prenatal cocaine exposure, the present study established the route of drug administration and the doses to be used for pregnant C57BL/6 mice. Comparison of the effects of a high dose of cocaine (60 mg/kg) when gavaged or injected subcutaneously (SC) established patterns of pathology characteristic of administration route but no dominating logic for selecting one over the other route for prenatal studies; however, because of the fourfold greater brain levels, with no evidence of greater pathology, the SC route was selected. When injected daily during gestation days 12-18, the period of prenatal development of dopamine systems, cocaine at doses producing plasma concentrations consistent with its stimulatory effects reduced food ingestion and weight gains during pregnancy and fetal body and brain weights at term. The extent of these reductions was comparable to reports on babies exposed to cocaine prenatally. Furthermore, the present study suggests that maternal undernutrition is not a likely mediator of these perinatal effects and that differences in the amount of cocaine exposure may cause the contrasting effects of maternal cocaine noted in the human literature.

The lethal effects of ethanol and cocaine and their combination in mice: implications for cocaethylene formation

The HS line of mice was used to determine the LD50 values for cocaine and ethanol, as well as for cocaethylene, the enzymatic product of their coadministration. The LD50 of cocaethylene was found to be significantly lower than that of cocaine, and both were more potent in their lethality than ethanol. When a low-lethality dose of cocaine was administered with a nonlethal dose of ethanol, the result was a significant increase in the prevalence of lethality. Thus, the lethal effects of the dose of cocaine used were increased by the dose of ethanol administered such that the two drugs in combination were equipotent to cocaethylene. The results are discussed in light of the ability of the liver, via transestification, to rapidly form cocaethylene from cocaine in addition to ethanol's ability to decrease the catabolism of cocaine. Thus, the possibility exists that the increased lethality observed is produced by both the production of the more lethal cocaethylene and sustained levels of cocaine.

Premorbid behaviors produced by cocaine, ethanol and cocaethylene in the mouse

1. The premorbid behaviors produced by the administration of cocaine, ethanol, their combination, as well as a metabolite produced by their co-administration, viz. cocaethylene, were defined, determined and quantified in the HS strain of mice. 2. The LD50 for ethanol was 9.71 g/kg in males and 9.45 g/kg in females, whereas the LD50 values in male and female mice for cocaine were 101.55 and 90.00 mg/kg, respectively. 3. The data indicate that clonic-tonic seizures continued into status epilepticus after cocaine administration and prior to cocaine-induced lethality. In contrast, administration of the cocaine-ethanol metabolite cocaethylene produced status epilepticus without producing clonic-tonic seizures yet still resulted in lethality. 4. Thus, both cocaine and cocaethylene may produce their lethal effects in mice through neuro-regulatory mechanisms mediating protracted seizure induction.

Alcohol-induced brain growth restrictions (microencephaly) were not affected by concurrent exposure to cocaine during the brain growth spurt

The prevalence of concomitant use of alcohol and cocaine among drug abusers has raised concern about the possible increased risk of fetal damage. The aim of this study was to assess the interactive effects of alcohol and cocaine on lethality, somatic growth, and brain growth using an animal model system. Sprague-Dawley rat pups were used as subjects. They were randomly assigned to 1 of the 9 artificially reared groups which varied with respect to the combination treatments of cocaine (0, 40, or 60 mg/kg) and alcohol (0, 3.3, or 4.5 g/kg). All artificially reared pups were given daily cocaine and alcohol treatments during a major part of the brain growth spurt period (postnatal days 4-9). An additional group of suckled control animals raised by their natural dams was included to control for artificial rearing. The results are summarized as follows: 1) Drug-induced lethality was higher in cocaine-treated groups when compared with non-cocaine-treated groups, and the concurrent administration of high doses of alcohol and cocaine significantly increased the mortality rate. 2) Somatic growth, in terms of body weight, was not affected by alcohol, cocaine, or the combination of both drugs using the artificial rearing technique. 3) Alcohol exposure during this brain growth spurt period significantly reduced whole brain weight, as well as forebrain, cerebellum, and brain stem weights. 4) In contrast to alcohol, cocaine failed to exert a detrimental effect on brain weight measures during this early postnatal period.(ABSTRACT TRUNCATED AT 250 WORDS)